"I have this distinct memory of standing in the lobby, seeing these investors talking to each other," Freedman writes. "I sheepishly introduced myself, giving them the 30-second pitch on FlightCaster. They weren't rude, they weren't abusive, but they weren't hungry to talk to me."

Last month when Freedman launched 42Floors at Y Combinator, a lease listing site for businesses in need of office space, it was a much different experience.

"No business plans, not even pitch decks this time. One 2-1/2 minute pitch and a quick follow up meeting," he writes. "Seven figure seed rounds that can be closed within days and oversubscribed 2x to 3x. Founders with no experience fundraising and no pre-existing networks, making connections with top tier guys. It was really a sight to see."

Freedman says one investor eager to get in front of him before his round closed was very persistent. The investor emailed Freedman four times, texted three times, called him and sent him a LinkedIn message.